Plaster wall board



m n27. msww C. R. BlRDSEY PLASTER WALLBOARD Filed Oct. 10, 1921 IN VEN TOR. mar/r5 i fla eiy.

' BY (f7 I A TTORNEYS.

Patented Nova. 29

rep STATE CHARLES R. BIRDSEY, OF HiNSDALE, ILLINOIS.

PIJASTER WALL BOARD.

Application filed October 10, 19 21. SeriaI No. 506,676.

This invention relates to improvements in plaster wall boards and more particularly to the formation of the longitudinal edges thereof.

It is an object of this invention to producea plaster boardthat may be readily used as a Wall board, that is, a prepared board that may be secured to the studdin of a building in the lace of laths an then plastered over be ore painting or papering or may be painted or paperedafterapplication without the necessity of first giving it a covering of plaster.

While the preferred form of this invention is illustrated upon the accompanying sheet or drawing, yetminor detail changes may be made without departing from the sco e thereof.

n the drawings Figure 1 is a view in cross-section of this improved plaster wallboard with parts broken away.

Figure 2 is a perspective view of Figure 1 illustrating the longitudinal and transverse edges.

Figure 3 is a view illustrating in cross-sec! tion the adjoining edges of ad acent boards after application to a wall.

Figure a is a view similar to Figure 3 illustrating the application of a filling compound.

In carryin out this invention the plaster wallboard is armed with a composition body 1, preferably plaster, between cover sheets 2 and 3, preferably of paper. The longitudinal edges on each side are covered and protected by partially bending back each cover sheet upon itself so that the bent back portions 4 and 5 overlap or engage at their ends, as shownin Figure 1, to hold the body from bein forced out between the cover sheets or from exuding between the edges of the cover sheets during fabrication and assist in maintaining the board of uniform thickness. ft is preferable to score each cover sheet adjacent each longitudinal edge before passing it into the mac inefor making the board and then bending the margins at the ed es partially back upon the body of each s eet, along the scoring, as they pass through the machine, so that the board will be of uniform width.

board of uniformwidthand't e-construction of the partially bent back margins at the edges insures uniform thickness along the longitudinal edges of the board. When used ,as a plaster-board and nailed directly to the studding 7 it-is customary to leave a \slight opening between the'edges of the adacent boards and the grooved edges will fornr pockets, such as 6 in Figure 3, into which the plaster covering will anchor and bond the boards and the covering more firmly together. When used as a wallboard the edges being straight, the boards may be applied clo'se to ether and nailed in place so that the boar s may be painted or papered and the edges being of the same thickness throughout as the body of the board, the J applied boards will present an uninterrupted fiat surface to receive the paint or paper. Also when used as a wallboard, in itself presenting the finished wall without plastermg over, the edges can be spaced slightly a art and the pocket 6 filled with a crack filing compound 8, as shown in Figure 4.

This pocketfi forming a key locked recepta cle for holding the crack filler in place, so that it will present at all times a true flush face with the adjoining board.

What I claim is: I y

1. A plaster board having a composition body and coverings on each side with the margins at the side edges of the coverings partially bent back upon themselves at an angle to each other to form grooved edges.

2. A plaster board having a composition body and coverings on each 'side with the margins at the side edges of the coverings partially bent back upon themselves at an angle to each other and contacting with each other to form grooved edges.

3. A plaster board comprising a composition body and a covering on each side, said -coverings being scored adjacent the margins of each longitudinal edge and the margins of each longitudinal edge partially bent back upon themselves at an angle to each other along the scoring, producing a board of uniform width with grooved edges.

4. A plaster board having a composition body and coverings on each side with the margins of the coverings at the side edges folded against the body and meeting at an angle to each other.

5. A plaster board comprising a plaster body and a cover sheet at each face side thereof folded over an edge of said body to form a depression along said edge.

6. In a plaster board of the kind-described and in combination, a plaster body and cover sheets at the face sides thereof, said sheets folded over and inwardly on the edge of the body at an acute angle, the widths of the sheets being greater than the width of the body and sufficient to permit the foldedover portions to be brought together and substantially engage to provide a pronounced groove at the edge of the board and entirely int-losing the plaster body.

7. A plaster board consisting of a plaster body provided with a covering inclosing the faces and opposite side edges, and having 15 a depression at each side edge.

8. The combination of a plurality of plaster boards arranged edge-to-edge, each having an edge groove at their juncture, of a key of suitable material inserted in said grooves for locking the parts against relative transverse movement.

9. The combination comprising a pair of plaster boards each consisting of a body-of plaster enveloped by covering material, said oards being placed in substantially abutting relation and having recesses in their adjacent edges, a joint filler covering the joint between said boards and keyed Within said recesses.

CHARLES R. BIRDSEY. 

